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<a href="_c_p_u_2_pooling_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno">    1</span><span class="preprocessor">#ifndef SHARK_CORE_IMAGES_CPU_POOLING_2D_H</span></div>
<div class="line"><a id="l00002" name="l00002"></a><span class="lineno">    2</span><span class="preprocessor">#define SHARK_CORE_IMAGES_CPU_POOLING_2D_H</span></div>
<div class="line"><a id="l00003" name="l00003"></a><span class="lineno">    3</span> </div>
<div class="line"><a id="l00004" name="l00004"></a><span class="lineno">    4</span><span class="preprocessor">#include &lt;<a class="code" href="_base_8h.html">shark/LinAlg/Base.h</a>&gt;</span></div>
<div class="line"><a id="l00005" name="l00005"></a><span class="lineno">    5</span><span class="preprocessor">#include &lt;<a class="code" href="_exception_8h.html">shark/Core/Exception.h</a>&gt;</span></div>
<div class="line"><a id="l00006" name="l00006"></a><span class="lineno">    6</span><span class="preprocessor">#include &lt;<a class="code" href="_shape_8h.html">shark/Core/Shape.h</a>&gt;</span></div>
<div class="line"><a id="l00007" name="l00007"></a><span class="lineno">    7</span><span class="keyword">namespace </span><a class="code hl_namespace" href="namespaceshark.html" title="AbstractMultiObjectiveOptimizer.">shark</a>{</div>
<div class="foldopen" id="foldopen00008" data-start="{" data-end="}">
<div class="line"><a id="l00008" name="l00008"></a><span class="lineno"><a class="line" href="namespaceshark_1_1image.html">    8</a></span><span class="keyword">namespace </span>image{</div>
<div class="line"><a id="l00009" name="l00009"></a><span class="lineno">    9</span><span class="keyword">template</span>&lt;<span class="keyword">class</span> T&gt;</div>
<div class="foldopen" id="foldopen00010" data-start="{" data-end="}">
<div class="line"><a id="l00010" name="l00010"></a><span class="lineno"><a class="line" href="namespaceshark_1_1image.html#a4575c29d1700b08ba700892f506c2491">   10</a></span><span class="keywordtype">void</span> <a class="code hl_function" href="namespaceshark_1_1image.html#a4575c29d1700b08ba700892f506c2491">maxPooling</a>(</div>
<div class="line"><a id="l00011" name="l00011"></a><span class="lineno">   11</span>    blas::dense_matrix_adaptor&lt;T const, blas::row_major, blas::continuous_dense_tag, blas::cpu_tag&gt; inputs, </div>
<div class="line"><a id="l00012" name="l00012"></a><span class="lineno">   12</span>    <a class="code hl_class" href="classshark_1_1_shape.html" title="Represents the Shape of an input or output.">Shape</a> <span class="keyword">const</span>&amp; shape,</div>
<div class="line"><a id="l00013" name="l00013"></a><span class="lineno">   13</span>    <a class="code hl_class" href="classshark_1_1_shape.html" title="Represents the Shape of an input or output.">Shape</a> <span class="keyword">const</span>&amp; patchSize,</div>
<div class="line"><a id="l00014" name="l00014"></a><span class="lineno">   14</span>    blas::dense_matrix_adaptor&lt;T, blas::row_major, blas::continuous_dense_tag, blas::cpu_tag&gt; outputs</div>
<div class="line"><a id="l00015" name="l00015"></a><span class="lineno">   15</span>){</div>
<div class="line"><a id="l00016" name="l00016"></a><span class="lineno">   16</span>    std::size_t depth = shape[2];</div>
<div class="line"><a id="l00017" name="l00017"></a><span class="lineno">   17</span>    std::size_t outputHeight = shape[0]/patchSize[0];</div>
<div class="line"><a id="l00018" name="l00018"></a><span class="lineno">   18</span>    std::size_t outputWidth = shape[1]/patchSize[1];</div>
<div class="line"><a id="l00019" name="l00019"></a><span class="lineno">   19</span>    std::size_t outputPixels = outputWidth * outputHeight;</div>
<div class="line"><a id="l00020" name="l00020"></a><span class="lineno">   20</span>    <a class="code hl_define" href="_exception_8h.html#a42a6a50e4d06c00d60fbca5333f40768">SIZE_CHECK</a>(outputs.size2() == outputPixels * depth);</div>
<div class="line"><a id="l00021" name="l00021"></a><span class="lineno">   21</span>    </div>
<div class="line"><a id="l00022" name="l00022"></a><span class="lineno">   22</span>    <span class="comment">//for all images</span></div>
<div class="line"><a id="l00023" name="l00023"></a><span class="lineno">   23</span>    <span class="keywordflow">for</span>(std::size_t img = 0; img != inputs.size1(); ++img){</div>
<div class="line"><a id="l00024" name="l00024"></a><span class="lineno">   24</span>        <span class="comment">//Extract single images and create matrices (pixels,channels)</span></div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno">   25</span>        <span class="keyword">auto</span> imageIn = to_matrix(row(inputs,img), shape[0] * shape[1], depth);</div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno">   26</span>        <span class="keyword">auto</span> imageOut = to_matrix(row(outputs,img), outputHeight * outputWidth, depth);</div>
<div class="line"><a id="l00027" name="l00027"></a><span class="lineno">   27</span>        <span class="comment">//traverse over all pixels of the output image</span></div>
<div class="line"><a id="l00028" name="l00028"></a><span class="lineno">   28</span>        <span class="keywordflow">for</span>(std::size_t p = 0; p != outputPixels; ++p){</div>
<div class="line"><a id="l00029" name="l00029"></a><span class="lineno">   29</span>            <span class="keyword">auto</span> pixel = row(imageOut,p);</div>
<div class="line"><a id="l00030" name="l00030"></a><span class="lineno">   30</span>            <span class="comment">//extract pixel coordinates in input image</span></div>
<div class="line"><a id="l00031" name="l00031"></a><span class="lineno">   31</span>            std::size_t starti = (p / outputWidth) * patchSize[0];</div>
<div class="line"><a id="l00032" name="l00032"></a><span class="lineno">   32</span>            std::size_t startj = (p % outputWidth) * patchSize[1];</div>
<div class="line"><a id="l00033" name="l00033"></a><span class="lineno">   33</span>            std::size_t endi = starti + patchSize[0];</div>
<div class="line"><a id="l00034" name="l00034"></a><span class="lineno">   34</span>            std::size_t endj = startj + patchSize[1];</div>
<div class="line"><a id="l00035" name="l00035"></a><span class="lineno">   35</span>            </div>
<div class="line"><a id="l00036" name="l00036"></a><span class="lineno">   36</span>            <span class="comment">//traverse the patch on the input image and compute maximum</span></div>
<div class="line"><a id="l00037" name="l00037"></a><span class="lineno">   37</span>            noalias(pixel) = row(imageIn, starti * shape[1] + startj);</div>
<div class="line"><a id="l00038" name="l00038"></a><span class="lineno">   38</span>            <span class="keywordflow">for</span>(std::size_t i = starti; i != endi; ++i){</div>
<div class="line"><a id="l00039" name="l00039"></a><span class="lineno">   39</span>                <span class="keywordflow">for</span>(std::size_t j = startj; j != endj; ++j){</div>
<div class="line"><a id="l00040" name="l00040"></a><span class="lineno">   40</span>                    std::size_t index = i * shape[1] + j;</div>
<div class="line"><a id="l00041" name="l00041"></a><span class="lineno">   41</span>                    noalias(pixel) = max(pixel,row(imageIn, index));</div>
<div class="line"><a id="l00042" name="l00042"></a><span class="lineno">   42</span>                }</div>
<div class="line"><a id="l00043" name="l00043"></a><span class="lineno">   43</span>            }</div>
<div class="line"><a id="l00044" name="l00044"></a><span class="lineno">   44</span>        }</div>
<div class="line"><a id="l00045" name="l00045"></a><span class="lineno">   45</span>    }</div>
<div class="line"><a id="l00046" name="l00046"></a><span class="lineno">   46</span>}</div>
</div>
<div class="line"><a id="l00047" name="l00047"></a><span class="lineno">   47</span> </div>
<div class="line"><a id="l00048" name="l00048"></a><span class="lineno">   48</span><span class="keyword">template</span>&lt;<span class="keyword">class</span> T&gt;</div>
<div class="foldopen" id="foldopen00049" data-start="{" data-end="}">
<div class="line"><a id="l00049" name="l00049"></a><span class="lineno"><a class="line" href="namespaceshark_1_1image.html#ad16d75e2efb8418fd83408f8fa922d47">   49</a></span><span class="keywordtype">void</span> <a class="code hl_function" href="namespaceshark_1_1image.html#ad16d75e2efb8418fd83408f8fa922d47">maxPoolingDerivative</a>(</div>
<div class="line"><a id="l00050" name="l00050"></a><span class="lineno">   50</span>    blas::dense_matrix_adaptor&lt;T const, blas::row_major, blas::continuous_dense_tag, blas::cpu_tag&gt; inputs, </div>
<div class="line"><a id="l00051" name="l00051"></a><span class="lineno">   51</span>    blas::dense_matrix_adaptor&lt;T const, blas::row_major, blas::continuous_dense_tag, blas::cpu_tag&gt; coefficients, </div>
<div class="line"><a id="l00052" name="l00052"></a><span class="lineno">   52</span>    <a class="code hl_class" href="classshark_1_1_shape.html" title="Represents the Shape of an input or output.">Shape</a> <span class="keyword">const</span>&amp; shape,</div>
<div class="line"><a id="l00053" name="l00053"></a><span class="lineno">   53</span>    <a class="code hl_class" href="classshark_1_1_shape.html" title="Represents the Shape of an input or output.">Shape</a> <span class="keyword">const</span>&amp; patchSize,</div>
<div class="line"><a id="l00054" name="l00054"></a><span class="lineno">   54</span>    blas::dense_matrix_adaptor&lt;T, blas::row_major, blas::continuous_dense_tag, blas::cpu_tag&gt; derivatives</div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno">   55</span>){</div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno">   56</span>    std::size_t depth = shape[2];</div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno">   57</span>    std::size_t outputHeight = shape[0]/patchSize[0];</div>
<div class="line"><a id="l00058" name="l00058"></a><span class="lineno">   58</span>    std::size_t outputWidth = shape[1]/patchSize[1];</div>
<div class="line"><a id="l00059" name="l00059"></a><span class="lineno">   59</span>    std::size_t outputPixels = outputWidth * outputHeight;</div>
<div class="line"><a id="l00060" name="l00060"></a><span class="lineno">   60</span>    <a class="code hl_define" href="_exception_8h.html#a42a6a50e4d06c00d60fbca5333f40768">SIZE_CHECK</a>(coefficients.size2() == outputPixels * depth);</div>
<div class="line"><a id="l00061" name="l00061"></a><span class="lineno">   61</span>    <span class="comment">//for all images</span></div>
<div class="line"><a id="l00062" name="l00062"></a><span class="lineno">   62</span>    <span class="keywordflow">for</span>(std::size_t img = 0; img != inputs.size1(); ++img){</div>
<div class="line"><a id="l00063" name="l00063"></a><span class="lineno">   63</span>        <span class="comment">//Extract single images and create matrices (pixels,channels)</span></div>
<div class="line"><a id="l00064" name="l00064"></a><span class="lineno">   64</span>        <span class="keyword">auto</span> imageCoeffs = to_matrix(row(coefficients,img),  outputHeight * outputWidth, depth);</div>
<div class="line"><a id="l00065" name="l00065"></a><span class="lineno">   65</span>        <span class="keyword">auto</span> imageIn = to_matrix(row(inputs,img), shape[0] * shape[1], depth);</div>
<div class="line"><a id="l00066" name="l00066"></a><span class="lineno">   66</span>        <span class="keyword">auto</span> imageDer = to_matrix(row(derivatives,img), shape[0] * shape[1], depth);</div>
<div class="line"><a id="l00067" name="l00067"></a><span class="lineno">   67</span>        <span class="comment">//traverse over all pixels of the output image</span></div>
<div class="line"><a id="l00068" name="l00068"></a><span class="lineno">   68</span>        <span class="keywordflow">for</span>(std::size_t p = 0; p != outputPixels; ++p){</div>
<div class="line"><a id="l00069" name="l00069"></a><span class="lineno">   69</span>            std::size_t starti = (p / outputWidth) * patchSize[0];</div>
<div class="line"><a id="l00070" name="l00070"></a><span class="lineno">   70</span>            std::size_t startj = (p % outputWidth) * patchSize[1];</div>
<div class="line"><a id="l00071" name="l00071"></a><span class="lineno">   71</span>            std::size_t endi = starti + patchSize[0];</div>
<div class="line"><a id="l00072" name="l00072"></a><span class="lineno">   72</span>            std::size_t endj = startj + patchSize[1];</div>
<div class="line"><a id="l00073" name="l00073"></a><span class="lineno">   73</span>            </div>
<div class="line"><a id="l00074" name="l00074"></a><span class="lineno">   74</span>            <span class="comment">//traverse the patch on the input image and compute arg-max for each channel</span></div>
<div class="line"><a id="l00075" name="l00075"></a><span class="lineno">   75</span>            <span class="keywordflow">for</span>(std::size_t c = 0; c != depth; ++c){</div>
<div class="line"><a id="l00076" name="l00076"></a><span class="lineno">   76</span>                std::size_t maxIndex =  starti * shape[1] + startj;</div>
<div class="line"><a id="l00077" name="l00077"></a><span class="lineno">   77</span>                <span class="keywordtype">double</span> maxVal = imageIn(maxIndex,c);</div>
<div class="line"><a id="l00078" name="l00078"></a><span class="lineno">   78</span>                <span class="keywordflow">for</span>(std::size_t i = starti; i != endi; ++i){</div>
<div class="line"><a id="l00079" name="l00079"></a><span class="lineno">   79</span>                    <span class="keywordflow">for</span>(std::size_t j = startj; j != endj; ++j){</div>
<div class="line"><a id="l00080" name="l00080"></a><span class="lineno">   80</span>                        std::size_t index = i * shape[1] + j;</div>
<div class="line"><a id="l00081" name="l00081"></a><span class="lineno">   81</span>                        <span class="keywordtype">double</span> val = imageIn(index,c);</div>
<div class="line"><a id="l00082" name="l00082"></a><span class="lineno">   82</span>                        <span class="keywordflow">if</span>(val &gt; maxVal){</div>
<div class="line"><a id="l00083" name="l00083"></a><span class="lineno">   83</span>                            maxVal = val;</div>
<div class="line"><a id="l00084" name="l00084"></a><span class="lineno">   84</span>                            maxIndex = index;</div>
<div class="line"><a id="l00085" name="l00085"></a><span class="lineno">   85</span>                        }</div>
<div class="line"><a id="l00086" name="l00086"></a><span class="lineno">   86</span>                    }</div>
<div class="line"><a id="l00087" name="l00087"></a><span class="lineno">   87</span>                }</div>
<div class="line"><a id="l00088" name="l00088"></a><span class="lineno">   88</span>                <span class="comment">//after arg-max is obtained, update gradient</span></div>
<div class="line"><a id="l00089" name="l00089"></a><span class="lineno">   89</span>                imageDer(maxIndex, c) += imageCoeffs(p,c);</div>
<div class="line"><a id="l00090" name="l00090"></a><span class="lineno">   90</span>            }</div>
<div class="line"><a id="l00091" name="l00091"></a><span class="lineno">   91</span>        }</div>
<div class="line"><a id="l00092" name="l00092"></a><span class="lineno">   92</span>    }</div>
<div class="line"><a id="l00093" name="l00093"></a><span class="lineno">   93</span>}</div>
</div>
<div class="line"><a id="l00094" name="l00094"></a><span class="lineno">   94</span> </div>
<div class="line"><a id="l00095" name="l00095"></a><span class="lineno">   95</span> </div>
<div class="line"><a id="l00096" name="l00096"></a><span class="lineno">   96</span>}}</div>
</div>
<div class="line"><a id="l00097" name="l00097"></a><span class="lineno">   97</span> </div>
<div class="line"><a id="l00098" name="l00098"></a><span class="lineno">   98</span><span class="preprocessor">#endif</span></div>
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